Muffler



Aug. 24 1926.

P. H. WILKINSON MUFFLER Filed April 4. 1924 Patented Aug. 24, 1926.

UNITED STATES PAUL E. WILKINSON, 0]? LOS ANGELES, CALIFORNIA.

MUFFLER.

Application filed April 4,

This invention relates to mufliers for internal combustion engines.

An object of this invention is the provision of a mufller in which no surface is at right angles to the flow of gases through it.

Another object of this invention is to reduce the pressure of gases in the tail end of the mufiier to as nearly atmospheric as possible, so as to make practically no noise.

A further object of this invention is the provision of a mufiier, the end of the tail pipe of which projects beyond the rear end of an automobile to eliminate substantially F1 2, v igpmi and 5 are views similar to Fig. 2,

but s 0 all metallic echo and to allow. gases 'to be dispersed without obstruction.

A further object of this invention is the provision of a muflier, which receives hot gases under pressure from an engine, splits them with a minimum amount of turbulence, allows them to expand and cools them by contact with the comparatively large surface area of the muffler.

Another object of this invention is the provision of a muffler shaped to provide a stream-line path for the gases passing through it.

Another object of this invention is the provision of a mufiier, the exhaust end of which is fan-shaped in plan view and flat oval in cross section.

With the foregoing objects in view, together with such other objects and advantages as may vention consists in the construction and arrangement of parts hereinafter descrlbed and claimed and illustrated in the accompanying drawings, in which Figure 1 is a side elevation of,- a chassis showing my imroved muflier attached to the exhaust pipe of the engine,

Fig. 2 is a central longitudinal section of the expansion chamber of the mufller of my invention, I Fig. 3 is a section taken on line 3-3 of wing modifications of my invention, Fig. 6 is a plan view of the rear endof the mufller, and Fig. 7 is a view taken of Fig. 6 1n the direction of the arrow 7 Referring to the drawings'for a more detailed descri tion thereof, the numeral 10 indicates a c assis having an enginell, and an exhaust pipe 12. A- mufll'er 13 oimy 1nvention is secured at 14 to the exhaust pipe subsequently appear, this in- 1924. Serial No. 704,261.

12 close to the motor or engine, and extends beyond the rear end of the chassis, to eliminate substantially all metallic echo and to allow gases to be'emitted therefrom without any obstruction.

The muffler 13 of my invention comprises a pipe 15, one end of which is secured to the exhaust pipe 12, and the other end being affixed to a hollow cone 16 having a flange 17. -An elongated conical tube 18 having a flange'19 is secured to the cone 16 by bolts I 20. The muffler also comprises a conical baflle plate 21 having a flange 21 which is secured between the flanges 17 and 19. The baffle plate 21 is provided with a plurality of apertures 22 disposed according to any convenient arrangement, but formed adjacent to the outer edge only of the baffle plate, as clearly shown in Fig. 3. The total area of all the apertures 22 is preferably greater than the area of the entrance to the mufiler.

' The form of mufller, shown in Fig. 2, comprises a second conical baffle plate 23 extending to the inner periphery of the conical tube 18 and secured thereto in any suitable manner. The bafile plate 23 is providthe baflie plate 21 and extends to the periphery of the muflier at the junction of the cones 16 and 18.

The baflie plate 21 may be secured in several manners within the mufller. As illustratedin Fig. 3, the bafiie plate is provided with a flan e 21 which can be inserted between the anges at the bases of the two cones 16 and 18 and secured therebetween. As shownin Figs. 2, 4 and 5, the ed e of the baflie plate instead of having the ange 21, may contact with the interior of the shell at the conti ous bases of the cones 16 and 18. By ma ing the bafl'le plate'21 of the proper size, its edge may be effectively clamped in position upon tightening the nuts 20 u on the bolts 19. Such tightening under 0 inary circumstances will rigidly clamp the bafile plate within the muffler. If desired, the edge of the baflie plate 21 can be spot-welded to one or both of the cones. The baffle plate 23 shown in Fig.2 can be secured within the mufller in either of two manners. This baflile plate can be forced rearwardly within the cone 18 toward its reduced end and the edge of the bafiie plate will wedge against the interior surface of the cone 18. This is usually sufiicient to properly maintain the baffle plate 23 in position. If desired, the edge of the baflie plate 23 can .be spot-welded or otherwise secured against the interior of the 'frusto-conical section 18. l

The mufiler of my invention comprises a tail pipe 28, the rear end of which is formed as shown in Figs. 6 and 7, these figures showing the end to be fan-shaped in plan view and to be flat oval in cross section,

-wherefrom the gases enter the atmosphere in a thin fan-shaped stream, which is readily dispersed with little noise. The end portion of the tail pipe may be integral with the pipe itself.

' The mufiler of my invention is'preferably adapted to have a greater diameter at all points than the diameter of the exhaust pipe to which it is connected in order to cool the engine gases as rapidly as possible, bothby expansion and by providing a larger cooling area. It will be appreciated that according to the description given, the mufiier of my invention provides a stream-line path for the gases passing through it, whereby back pressure is substantially eliminated.

Furthermore, the muffler of my invention takes the hot gases under pressure from the engine, splits them up with a minimum amount of turbulence, directs them as shown by the arrows in Figs. 2, 4 and 5, expands the gases, cools them rapidly due to the large area of the mufiler and emits them into the atmosphere with very little noise.

The apertures in the bafile plates, as previously stated, are preferably placed adjacent to the outer edges of the plates and are so positioned that the gases, in passing through the expansion chamber, are diverted towards the wall of the chamber, so that they may be cooled by the wall, which, being of metal, is a good heat conductor.

This invention has been described, but modifications thereof may be devised without departing from the spirit thereof, and it is to be understood that such modifications come within the scope of this invention.

What is claimed is 1. A muflier comprising a shell composed of two frusto-conical sections secured together base to base, the reduced end of one section constituting an inlet to said muflier and the reduced end, of the other section constituting an outlet, the conical section forming the outlet being materially longer than the section forming the inlet, and a conical baffle plate disposed within said shell, said baffle plate having its apex directed toward the inlet and having its edge abutting the interior of said shell, said baflle plate being perforated only around its edge, whereby gases entering the mufiler may be divided by the conical bafile plate, pass through the perforations at the edge of the bafiie plate and then be gradually converged by the outlet forming section of the shell toward the outlet.

2. A mufiler comprising a shell composed of two frusto-conical sections secured together base to base, the reduced end of one section constituting an inlet to said mufller and the reduced end of the other section constituting an outlet, the conical section forming the outlet being materially longer than the section forming the inlet, and conical bafil'e plates disposed within said shell, all of said bafile plates having their apexes directed toward the inlet, each bafile plate being perforated only adjacent its edge, whereby gases entering the mufller may be divided by the conical baflle plate, pass through the perforations at the edge of the bafiie plate'and then be gradually converged by the outlet forming section of the shell toward the outlet.

3. A mufller comprising a shell composed of two frusto-conical sections secured together base to base, the reduced end of one section constituting an inlet and the reduced end of the other section constituting an outlet, a conical baflle plate-within 'said shell having its edge at the abutting bases of said sections, said bafile late having its apex directed toward the inlet to the mufller and rated only adjacent its edge, and a second conical bafile plate having its edge secured to the interior of the outlet forming section, said second bafiie plate having its apex directed toward the inlet and being perforated only around its edge.

4. A mufiier comprising a shell formed of two frusto-conical sections secured together base to base, a conical bafile plate disposed within said shell having its edge engaging the shell at the contiguous bases of said sections, said bafiie plate having its apex directed toward the inlet to the mufiler and being perforated only adjacent its edge, and a second bafiie plate disposed between said bafile plate and the outlet from the mufiler, said second baflle plate being conical and having its apex directed toward the inlet to the mufiler and being perforated only adjacent its edge.

In testimony whereof I have signed my 7 name to this specification.

PAUL H. WILKINSON. 

